Codeigniter + Mysql Active Record查询ASC DESC订单

Question

I have three tables named:

at_category:

1. cat_id
2. name

at_category_taxonomy:

1. cat_taxonomy_id
2. cat_id
3. taxonomy

at_shop:

1. shop_id
2. shop_category

I want to join those three tables by counting result.

For example the category named as Electronic Shops in at_category table and the value will be stored in at_category_taxonomy table and the this category id's are having two shops in at_shop table. same as for remaining categories aaa, bbb, ccc etc...it may be having one or two shops else zero shops.

Example :

1. at_category

    ______________

    cat_id   name

     1       Electronic Shops
     2       Ice Cream Shops
    _______________

    2. at_category_taxonomy

    _______________________________________________

    cat_taxonomy_id   cat_id   taxonomy

      3                 1       Electronic Shops
      4                 2       Ice Cream Shops
    _______________________________________________

    3. at_shop

    ________________________________

    shop_id   shop_name   shop_category

     1            A         1 (ie.Electronic Shops) 
     2            B         1 (ie.Electronic Shops) 
     3            C         1 (ie.Electronic Shops) 
     4            D         2 (ie.Ice Cream Shops) 

    ________________________________

Now : The category Electronic Shops having 3 shops and Ice cream shops having 1 shop

Expecting output :

No.Of.Shops (ASC) (Desc)    Category Name   (ASC) (Desc)

     3                         Electronic Shops
     1                         Ice cream Shops 

When i click asc order in no.of shops column then the output will be

No.Of.Shops (ASC) (Desc)    Category Name   (ASC) (Desc)

     1                          Ice cream Shops   
     3                          Electronic Shops

This is vise verse for category name too.

now I want to display the result by count the number shops by desc order using codeigniter.

Answer 1

Write a method in a model like below.

public function get_shops_by_category($order_by_column='shop_cnt',$order_by_method='DESC'){ 
    $this->db->select('c.name,COUNT(s.shop_id) as shop_cnt');
    $this->db->from('at_category AS c');
    $this->db->join('at_shop AS s','c.cat_id = s.shop_category','left');
    $this->db->group_by("c.cat_id"); 
    $this->db->order_by("{$order_by_column}", "{$order_by_method}"); 
    return $this->db->get()->result();
}

Call the model method in controller . suppose my model name is Shop_model.So in controller I will write :

$order_by_method = (!empty($this->input->get($order_by_method))) ? $order_by_method : 'DESC';
$order_by_column = (!empty($this->input->get($order_by_column))) ? $order_by_column : 'shop_cnt';

$result = $this->shop_model->get_shops_by_category($order_by_column,$order_by_method);

on clikc you need to pass order_by_column value and order_by_method value in url

Answer 2

This is the model code:

<?php //if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Shop_model extends CI_Model {

    public function __construct(){
        parent::__construct();  
    }

    public function get_shops_by_category($order_by_column='shop_cnt',$order_by_method='DESC'){ 
        $this->db->select('c.name,COUNT(s.shop_id) as shop_cnt');
        $this->db->from('at_category AS c');
        $this->db->join('at_shop AS s','c.cat_id = s.shop_category','left');
        $this->db->group_by("c.cat_id"); 
        $this->db->order_by("{$order_by_column}", "{$order_by_method}"); 
        return $this->db->get()->result();
    } 

}

Below is the controller:

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Shop extends CI_Controller {

    public function __construct(){
        parent::__construct();
    }

    public function index(){
        $this->load->model('Shop_model');

        $order_by_method = $this->input->get('order_by_method', TRUE);
        $order_by_column = $this->input->get('order_by_column', TRUE);  
        if(empty($order_by_method)){
            $order_by_method = 'DESC';
        }
        if(empty($order_by_column)){
            $order_by_column = 'shop_cnt';
        }           

        $result = $this->Shop_model->get_shops_by_category($order_by_column,$order_by_method);
        echo '<pre>';
        print_r($result);
        //$this->output->enable_profiler(TRUE);
        //$this->load->view('welcome_message');
    }
}

/* End of file Shop.php */
/* Location: ./application/controllers/Shop.php */